Selective catalytic oxidation of unsaturated alcohols to carbonyl compounds

Abstract

Primary and secondary unsaturated alcohols are converted to their corresponding aldehydes and/or carboxylic acids and ketones respectively with alkali metal (per) halate, preferably sodium periodate, in the presence of ruthenium catalyst. The process is particularly useful in the oxidation of chrysanthemyl alcohol. Any unconverted intermediate aldehyde formed may be converted to the acid by recycling or by a separate oxidation step.

What is claimed: 
     
       1. Process for the oxidation of a primary unsaturated alcohol to its corresponding carboxylic acid wherein said primary alcohol is (a) an olefinically unsaturated alcohol selected from the group consisting of straight chain alcohols, branched chain alcohols, and cycloalkyl containing alcohols; or   (b) an aromatically unsaturated alcohol which contains an aryl alkyl functionality, which comprises contacting the same with a catalytic quantity of a ruthenium catalyst from the group consisting of RuO 2  and A 2  RuO 4  wherein A is an alkali metal cation in an amount of up to about 10 mols of said catalyst per 100 mols of said alcohol in an aqueous alkaline medium and with a substantially stoichiometric amount of an oxidizing agent selected from the group consisting of an alkali metal (per) halate and an alkali metal hypohalite to continually regenerate the A 2  RuO 4  oxidation catalyst throughout the oxidation reaction.   
     
     
       2. Process according to claim 1 wherein chrysanthemyl alcohol is oxidized at least in part to chrysanthemic acid. 
     
     
       3. Process according to claim 2 wherein the oxidizing agent comprises NaIO 4  and the catalyst comprises RuO 2 . 
     
     
       4. Process according to claim 2 wherein the oxidizing agent comprises NaIO 4  and the catalyst comprises Na 2  RuO 4 . 
     
     
       5. Process for the oxidation of chrysanthemyl alcohol to chrysanthemic acid which comprises contacting the alcohol in aqueous alkaline medium with a catalytic quantity of RuO 2  in an amount of up to about 10 mols per 100 mols of said alcohol and sodium periodate in substantially stoichiometric quantity to continually regenerate A 2  RuO 4  oxidation catalyst throughout the oxidation reaction wherein A is an alkali metal cation. 
     
     
       6. The process according to claim 5 wherein chrysanthemyl aldehyde, formed as by product in the oxidation, is subsequently converted by further oxidation to further quantities of chrysanthemic acid.